MARINE CRUSTACEANS. 451 



specifically from G. glahrous, this must be a question of interpretation in which we must agree 

 to differ; though, should he agree with me in considering G. glabrous as a variety only of 

 G. chiragra, I think it would be difficult to consider G. graphurus as anything but a variety 

 of the same species, standing a step beyond G. chiragra var. glabrous in its relation to 

 G. chiragra proper. 



A further point in which var. glabrous, var. mutatus, and var. graphurus differ from 

 G. chiragra is the greater elevation of the carinae, and the presence of two tubercles just 

 beyond the distal end of the median carina, which seem to be correlated ; an examination 

 of figures 6 — 9 and 10 — 11 will show the stages leading up to this, the carina first becoming 

 raised on a prominence of their own, and the posterior border of that prominence eventually 

 breaking forth into two tubercles in var. glabrous. I also give figures of two glabrous forms 

 (figs. 8 — -9) to illustrate some varying appearances of the three median carinae, showing 

 actual connection, or signs of connection, between the submedians and medians : and here I 

 would suggest that, from the point of view of consistency in the nomenclature of the carinae, 

 the carinae on each side of the median carina in G. chiragra proper should be called the 

 lateral carinae, corresponding to the external, or lateral, of the five carinae in var. glabrous 

 and var. graphurus, reserving the term submedians for the intermediate carinae in these 

 latter varieties. 



Second heading. I. Var. incipiens a, var. nov. PI. XXIII. fig. 10. 



In this the carinae are tumid as in var. tuinidus and without spines, but the median 

 carina shows the first signs of the ' anchor ' in the fact that, at its distal end, the sides 

 are slightly grooved and a small portion separated off; the lateral marginal teeth are also 

 present, but of small size only. 



This is represented by a female, length 16'5, in the collection of the Cambridge Museum 

 from Funafuti, Ellice Is., and is one out of some specimens referred to G. chiragra by 

 Mr Borradaile. I am permitted to figure this form by the courtesy of Dr S. F. Hai-mer, F.R.S. 



II. Var. incipiens b. PL XXIII. fig. 11. 



The carinae are swollen ; the median with a well-developed anchor, but no spine ; the 

 lateral marginal teeth well-developed. 



This is the form chosen by Dr de Man as the ty|je of the species, and figured by him 

 in Zool. Jahrh. Sgst. X. PI. XXXVIII. Fig. 77, and the same as the forms referred to 

 var. A (type) by Mr Borradaile in Willey's Zool. Results, Pt. IV. It is not represented in this 

 collection. 



III. Var. segregatus c. PI. XXIII. fig. 12. 



Forms the same as var. segregatus a, described on p. 92, but without a spine at the 

 distal end of the median carina. 



Not represented in this collection ; but, as stated above, I have seen specimens fi-om 

 the Macclesfield Bank up to .30 mm. in length, and others from Kelantan and Penang in 

 the Malay Peninsula up to 28 mm. 



IV. Var. glahrous pars. 



Carinae swollen, without any spines, or at best but tubercular rudiments of them. 

 G. 58 



